Sinker cap for circular knitting machines



July '7, 1959 E. ST. PIERRE 2,893,227

SINKER CAP FQR CIRCULAR KNITTING MACHINES Filed April 19, 1956 .ZL (if:vl/llllllllllllllaur a a- INVENTOR EUGENE 57 79/5225 Uni sd e PM EugeneSt. Pierre, Pawtucket, R.I., assignor to Hemphill Company, Pawtu'cket,11.1., a corporation of Massachusetts p i @Application April in, 1956,Serial No. 579,187 i 9 Claims; (Cl. 66-107) Thisinvention-concerns.circular knitting machines and, particularly, anirn'proveriientv in the sinker cap used in such machines.

A characteristic feature of a circular knitting machine is a slottedcylinder adapted to carry the needles which knit the fabric produced bythemachine. Secured to the top of the needle cylinder is a slottedsinker head supporting the sinkers which cooperate witlithe needles inthe knitting operation. The sinkers are reciprocated in the slots of thehead by means of cams which are carried by a sinker cap customarilysupported by the sinker head.

This arrangement calls for a running fit between the cap and the head.In the course of continued operation, the head and the cap both wear.Eventually, the fit becomes sloppy, and the cap becomes loose on thehead. The loose cap makes exact control of the sinkers by the camsunreliable and increases the difliculty of producing fabric of uniformstitch characteristics.

One of the principal objects of the present invention is to improve theconstruction of the sinker cap and its supporting means to overcome thisdifliculty. This is accomplished by providing, for the cap, vertical andlateral support which is independent of the head. An embodiment of theinvention is shown in the accompanying drawings, in which:

Figure 1 is a plan view of a sinker cap porting mechanism;

Figure 2 is a section along the lines 2-2 of Figure 1;

Figure 3 is a section along the lines 3--3 of Figure l; and

Figure 4 is a front view of the Figure 1.

The plan view of Figure 1 shows the invention as applied to theHemph-Lon model of the Banner knitting machine. The needle cylinder 11is shown supported by the circular base 12 of the machine. The sinkerhead 13 is shown in dotted lines underlying the sinker cap 14.

The cap 14 is held to, but not supported by, the head 13 by means ofthree brackets 15. The actual support of the cap is accomplished throughthree horizontal members 16, 17 and 18 secured, respectively, to thecarrier ring post 19, the yarn lever box 20, and an extension 21 of apick bracket.

The sectional view, Figure 2, shows a stitch ring 22 and one of thescrews 23 which secure this ring to the top of the cylinder. The stitchring is slotted to accommodate the sinkers 24 which are carried by thehead 13 and are reciprocated back and forth in individual slots of thehead by means of cams 25 carried by the cap 14.

The head 13 is secured rigidly to the top of the cylinder by means ofthree screws 26 which pass through counterbored holes in the head andclamp a ring 27 projecting from the top of the cylinder 11 between aprojection 28 of the head and a clamping plate 28a.

One of the brackets 15 which holds the cap 14 in a sliding fit to thehead 13 is shown in section in Figure 2 and in a front view in Figure 4.It comprises an angular and its suparea designated 4-4 of ice shapedbracket with one arm fitting into a groove in the head 13 and the otherscrewed to the cap 14.

"Brackets 15 merely hold the cap 14 to the head 13. In a running fit,they prevent the cap from flying oil? the head. The Weight of the caprests on vertical supporting ,elements 29 carried by the supportingmembers 16, 17

and 18. Elements 29 are shown as circular nubbins or buttons pressfitted into the supporting members. They have an upper polished bearingsurface upon which the under-surface of the cap 14 rests.

The supporting members 16, 17 and 18 also carry laterally eifectivebearing members or elements 30, shown as needle bearings. By a bearingelement we mean one wherein there is relative motion between thatelement and a second member whose movement is to be confined withincertain limits, These needle bearings are screwed into sliding shafts 31which pass through the center of the v adjustment. Horizontal adjustmentof the bearings 30, and conse-' members 16, 17 and 18. Set screw 32locks the needle bearing in position after it is screwed the desiredlength down into the shaft. This provides a means for Vertical quentlycentering of the cap 14, is accomplished by sliding each shaft 31 in andout of its supporting member. This movement is accomplished by turning athreaded stud 33 which screws into and out of the shaft 31. Stud 33 islocked to a plate 34, screwed to the end of the supporting member, bymeans of an outer shoulder 35 and an inner shoulder 36. Consequently,turning the slotted hex head of the stud, by means of either a wrench ora screw driver, moves the shaft in and out. In order to permit thismotion, the screw which secures the needle bearing 30 to the memberpasses through a bushing and an elongated slot in the supporting member.When proper adjustment of the shaft 31 has been accomplished, the screw33 is locked in position by means of a set screw 37.

The arrangement described above provides a rigid and adjustable support,featuring three-point horizontal and vertical bearings, for the sinkercap 14 which is independent of the sinker head 13 and prevents oneWearing upon the other, thus permitting a more reliable adjustment ofthe sinker cams and operation of the sinkers than has been possibleheretofore.

I claim:

1. In a circular knitting machine having a rotary needle cylinder andneedles in said cylinder; a radially grooved external sinker ring whichis secured to said cylinder, outside sinkers in said ring, an annularcap which is fitted upon the sinker ring and carries cams for operatingthe sinkers, a peripheral portion of the sinker ring being rotatablewithin the annular cap, at least three laterally effective bearingelements which are substantially equally spaced apart and are engagedwith the periphery of the annular cap to maintain the latter concentricwith respect to the sinker ring and the needle cylinder and stationarysupport means which has the said laterally effective bearing elementsattached thereto.

2. For a circular knitting machine having a rotatable needle bearingcylinder, a sinker bearing head fixed to said cylinder, a sinker cap,and means for supporting said cap free of said head which comprises aplurality of vertical supporting members and a plurality of laterallyeffective bearing members.

3. In a circular knitting machine having a sinker head and a sinker cap,and a plurality of horizontal means, independent of said head, eachhaving a vertical supporting member and a laterally effective bearingmember, said gergbers being adapted to support said cap free of said 4.Means for supporting the sinker cap of a circular knitting machine whichcomprises at least three horizontal members disposed at substantiallyequal distances around the cap, each of said members being provided witha vertical supporting member and a laterally eflective bearing member,said members being adapted to support said cap free of said head 5. Inacircular knitting. machine having. a-sinker head and a sinker. cap, atleast three supports, independent of the head, each having a horizontal.bearing. surface, for. supporting the cap free of the head.

6. In a circular knitting machine having. a sinker head and asinker cap,at least three laterally effective bearing members, independent of thehead, said members being adjustable to maintain said cap concentric withsaid head.

7.- In a circular knitting machine,. a needle hearing cylinder, aslotted sinker head fixed to said' cylinder, sinkers reciprocablymovable in the slots of said sinker head, and a sinker cap having, camsadapted to move said sinkers, said: sinker cap being held againstlateral movement with respect to said head by a plurality of. laterallyeifective bearing members bearing against its out side lateral surface,said members being, adapted to sup port said cap free of said head.

8.- In a circular knitting machine having a slotted needle bearingcylinder, needles reciprocably mounted in. the slots of said cylinder, aslotted sinker head concentric with and at the top of said cylinder,sinkers reciprocably mounted in the slots of said" sinker head, a sinkercap overlying said sinker head and carrying cams adapted to engage andoperate said sinkers, said sinker cap being vertically supported bymeans independent of said sinker head, and horizontally held by aplurality of laterally efiective bearing members independentlyadjustable to maintain said cap concentricwitlt said head.

9. In a circular knitting machine having a slotted needle bearing.cylinder, needlesreciprocably mounted in the slots of said cylinder, aslotted sinker head concentric with and at the top of said cylinder,sinkers reciprocably mounted in the slots of said sinker head, a sinkercap overlying said sinker head and carrying cams adapted to engage andoperate:- said sinkers,, said sinker cap being vertically supported bymeans independent of said sinker head, and horizontally held by aplurality of laterally efiective bearing members. independentlyadjustable to maintain said cap concentric with; sai'dihead", saidbearing members comprising needle bearings.

1,086,968" Wilcomb Feb. 10, 19I4

